Speed Throttle in Ubuntu

Running Ubuntu 8.04 on the laptop and the speed throttle application says the laptop does not support throttling.

This is somewhat correct because speed step is not available in the Celeron M family (mine is a 520 Merom) but there is another method. XP and VISTA speed throttle is available on this laptop (using winthrottle in XP, Toshiba drivers for VISTA).

So, is there an add-on for Ubuntu/Linux that will do the same as the windows and allow dropping processor speed on the fly? I've googled but found nothing.